Organocatalyzed Cyclopropanation of a-Substituted a,b-Unsaturated Aldehydes: Enantioselective Synthesis of Cyclopropanes Bearing a Chiral Quaternary Center - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Chemistry - A European Journal Année : 2010

Organocatalyzed Cyclopropanation of a-Substituted a,b-Unsaturated Aldehydes: Enantioselective Synthesis of Cyclopropanes Bearing a Chiral Quaternary Center

Résumé

An enantioselective cyclopropanation of a-substituted a,b-unsaturated aldehydes with bromomalonate has been successfully developed through a domino Michael/alkylation strategy. The method allows the efficient formation of cyclopropanes bearing a quaternary carbon stereocenter at the a-position of the aldehydes by using iminium/enamine catalysis and gives a nice extension on the organocatalytic cyclopropanation of bromomalonate and a,b-unsaturated aldehydes previously reported by other groups. Very good yields (up to 81%) and enantioselectivities (up to 97% ee) have been obtained. The optically active cyclopropane derivatives are of high synthetic interest as useful targets for further elaboration into more complex structures.

Domaines

Chimie organique

Dates et versions

hal-00490024 , version 1 (07-06-2010)

Identifiants

Citer

Vincent Terrasson, Arie van Der Lee, Renata Marcia de Figueiredo, Jean-Marc Campagne. Organocatalyzed Cyclopropanation of a-Substituted a,b-Unsaturated Aldehydes: Enantioselective Synthesis of Cyclopropanes Bearing a Chiral Quaternary Center. Chemistry - A European Journal, 2010, 16 (26), pp.7875-7880. ⟨10.1002/chem.201000334⟩. ⟨hal-00490024⟩
168 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More